Hydrazides from nitro compounds

Deuterio-3-nitro-l,6-naphthyridine (168) was prepared from 4-chloro-3-nitro-l,6-naphthyridine (166) by a reaction with tosyl hydrazide and subsequent hydrolysis of the 4-tosylhydrazino derivative (167) with Na2C03/ D20 solution (83RTC359). 7-Deuterio-l,8-naphthyridin-2(lH)-one was prepared by heating l,8-naphthyridin-2(lH)-one with deuterium oxide at 230°C for 35 h (85JHC761). This deuterio compound could be converted into 2-chloro-(or 2-ethoxy-) 7-deuterio-3,6-dinitro-l,8-naphthyridine. 

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